Fabrication of bio-microelectrodes for deep-brain stimulation using microfabrication and electroplating process

This paper presents a novel bio-microelectrode structure for deep-brain stimulation in neural disorder treatment and a method for connecting PtIr₁₀ microwires onto this microelectrode. The microelectrode is consisted of four stimulation sites fabricated by microfabrication process and two recording sites formed by encapsulation technique. After Si-based microelectrode is fabricated through microfabrication process, electroplating is used to connect microwires to the microelectrode through a Pt film electroplated on the microwires that is fixed in the grooves of the microelectrode. Scanning electron microscopy revealed that the microwire was connected tightly to the microelectrode by electroplating, and the tensile strength of the microwire connection reached up to 0.375 MPa when the thickness of the Pt film was 3 μm and above. Cyclic voltammograms showed that the microelectrode and the electroplated connection had fine electrochemical stability. The results indicated that the electroplating could be used as an effective method for connecting PtIr₁₀ microwires with Pt film microelectrode in deep-brain stimulation.